Oil prices fell Wednesday following a government report showing that U.S. crude inventories increased last week, reflecting continuing weak demand. Light sweet crude oil for September delivery fell nearly $1 to just above $71 a barrel in midday trading on the New York Mercantile Exchange. Oil prices briefly touched $75 on Tuesday before falling 3 percent. The Energy Department reported that U.S. crude supplies rose by 200,000 barrels last week. The same report a week ago showed a big and unexpected decline in oil inventories, which sent prices soaring.